Therapeutic regimen

ABSTRACT

The present invention relates to dosing regimen of a new antimalarial drug, as monotherapy or combination therapy.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/669,275, filed Oct. 30, 2019 which claims the benefit of priority toU.S. application Ser. No. 15/961,394, filed Apr. 24, 2018, and IndianPatent Application No. 201711014459, filed Apr. 24, 2017, the contentsof which is incorporated herein by reference.

FIELD OF THE INVENTION

The invention provides an imidazolepiperazine, such as2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone(KAF156), or a pharmaceutically acceptable salt thereof, for use in theprevention or treatment of malaria, optionally in combination withanother anti-malaria drug. The invention relates to methods ofpreventing, treating, delaying the symptoms or ameliorating theconditions associated with malaria, comprising administering to asubject in need thereof said imidazolepiperazine or a pharmaceuticallyacceptable salt thereof, optionally in combination with anotheranti-malaria drug. Specifically, the invention provides new dosingregimen of2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone,or a pharmaceutically acceptable salt thereof, and combinationscomprising said compound, and another anti-malaria drug.

BACKGROUND OF THE INVENTION

Malaria is one of the most important infectious diseases, whichthreatens about 3.2 billion people, almost half of the world'spopulation. Despite increasing international efforts for malariacontrol, in 2015, there were 214 million cases worldwide of malaria and438 000 deaths according to the latest estimates of the World HealthOrganization. Sub-Saharan Africa carries a disproportionately high shareof the global malaria burden. In 2015, the region was home to 88% ofmalaria cases and 90% of malaria deaths. Also, in areas with hightransmission of malaria, children under 5 are particularly susceptibleto infection, illness and death; more than two thirds (70%) of allmalaria deaths occur in this age group (306 000 estimates deaths in2015).

Malaria is an infectious disease caused by four protozoan parasites:Plasmodium falciparum; Plasmodium vivax; Plasmodium ovale; andPlasmodium malaria. These four parasites are typically transmitted bythe bite of an infected female Anopheles mosquito. Malaria is a problemin many parts of the world and over the last few decades the malariaburden has steadily increased. An estimated 1-3 million people die everyyear from malaria—mostly children under the age of 5. This increase inmalaria mortality is due in part to the fact that Plasmodium falciparum,the deadliest malaria parasite, has acquired resistance against nearlyall available antimalarial drugs, with the exception of the artemisininderivatives.

Malaria is characterized by fever, headache, muscle ache, back pain,joint pains, nausea, sometimes vomiting and coughs; in severe case itleads to coma and finally it causes death.

Standard antimalarial drugs such as chloroquine (CQ), pyrimethamine(PYR), sulfadoxine (SFDX) and mefloquine (MEF) have become largelyineffective in many malaria endemic regions. The only exceptions are theartemisinin-based combination therapies (ACTs) such as Novartis'Coartem®/Riamet® and Eurartesim®, current standard-of-care for P.falciparum malaria.

Coartem® is a fixed combination of artemether, an artemisininderivative, and lumefantrine. Dosing is weight-based and the standarddose is composed of 80 mg artemether and 480 mg lumefantrine twice dailyfor three days. As stated in the prescribing information Coartem must beadministered with high fat food, since food is known to increase thebioavailability of lumefantrine by up to 16-fold and of artemether by upto 3-fold. The administration of Coartem with food is also important toachieve sufficient exposure of lumefantrine up to day 7, which isrequired for high cure rate. In acute malaria illness and in malariaendemic countries, non-adherence to this treatment requirement couldlead to treatment failure.

Some recent reports (Menard et al 2016; A worldwide map of Plasmodiumfalciparum K13-Propeller polymorphisms; N. Engl. J. Med;374(25):2453-64) suggest that decades of continuous use of artemisininand bisquinoline derivatives as monotherapies may have fostered theemergence of drug resistance in Plasmodium species in Southeast Asia.Reduced in vitro susceptibility of P. falciparum to artemisinin in thisregion has been documented. Recent studies showed that artemisininresistance extends over more of southeast Asia than had previously beenknown, and is now present close to the border with India (Menard et al2016). If widespread artemisinin drug resistance was to occur, malariapharmacotherapy would be severely impaired. This finding signifies thatspread of resistance is inevitable, thus there is urgent need for newantimalarials with new mechanism of actions (Tun et al 2015; Spread ofartemisinin-resistant Plasmodium falciparum in Myanmar: across-sectional survey of the K13 molecular marker; Lancet Infect Dis;15(4):415-21). In addition, current falciparum malaria treatmentsrequire at least a 3-day dosing regimen which may contribute totherapeutic non-compliance in some patients. Indeed, patients often haveresolution of clinical symptoms within 1 to 2 days and may neglecttaking final doses. This may contribute to the development of drugresistance.

2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone(KAF156) is the first drug from a different and novel class of drugscalled imidazolepiperazines. This compound is structurally distinct fromcurrently marketed antimalarial drugs and other experimentalantimalarial compound classes currently in development. The mechanism ofaction of KAF156 is still being characterized, but may be related to apreviously uncharacterized gene (Plasmodium falciparum cyclic amineresistance locus, Pfcarl). KAF156 kills/inhibits the erythrocyticreplication life cycle stages (blood stages) of the two main causativeagents of human malaria, P. falciparum and P. vivax, both at lownanomolar EC50s (in vitro). In addition, KAF156 has shown activity inliver stage models of Plasmodium infection, conferring causalprophylactic protection in animal infection models. Limited evidence ofgametocyticidal activity may confer transmission blocking activity.KAF156 has not demonstrated activity against liver hypnozoites andtherefore has a low probability to be used for a radical cure for P.vivax. Also, KAF156 is equally potent against drug-sensitive and a broadpanel of drug resistant malaria strains (Kuhen et al 2014 “KAF156 is anantimalarial clinical candidate with potential for use in prophylaxis,treatment, and prevention of disease transmission; Antimicrobial Agentsand Chemotherapy; 2014; 58(9):5060-5067).

By killing the malaria parasite at its early, asymptomatic liver stage,KAF156 has a potential to serve as a prophylactic treatment, preventingthe disease to spread into the blood stream, and thus to pass into amosquito which could otherwise infect another human.

KAF156 was previously tested in malaria in uncomplicated adult malariapatients, either in a 3 day dosing with a dose of 400 mg/day (patientsaffected by with P. vivax or P. falciparum) or in a single dosing with adose of 800 mg (patients affected by with P. falciparum) (NCT01753323).The results are published in White et al. (New England Journal ofMedicine, 375; 12, 2016). No serious adverse event was reported. Thestudy shows that KAF156 has activity against vivax and falciparummalaria, including artemisinin-resistant parasites. One patient who hadreceived the single 800-mg dose had repeated vomiting and was withdrawnfrom the study. Five other patients vomited after receiving the single800-mg dose, as compared with 1 patient with P. falciparum malaria inthe multiple-dose cohort. Four patients who received the single 800-mgdose reported nausea, as compared with 1 patient with P. falciparummalaria in the multiple-dose cohort. Furthermore KAF156 was shown to berapidly absorbed while having a longer half-life of about 50 hours.Antimalarial drugs that are eliminated rapidly (terminal eliminationhalf-life inferior to 3 days) usually cannot cure falciparum malaria ina single dose.

In view of the foregoing, there is a strong medical need for newtherapies for malaria, which is a very common disease responsible ofsubstantial morbidity and mortality. It is desirable to develop newtreatment for that disease, including in areas where resistance to ACTsis emerging. Simplifying regimens by developing treatments that can beused in a once daily dose for less than 3-day administration can improvetreatment success and reduce probability of developing resistance viaimproved adherence and thus accelerate malaria eradication.

SUMMARY OF THE INVENTION

The invention addresses these needs by providing novel therapeuticregimen which employ novel new therapeutically effective amounts of animidazolepiperazine, such as2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone(KAF156), or a pharmaceutically acceptable salt thereof; and new dosingregimens of KAF156, that are particularly adequate for short treatmentduration and can be used in combination with another anti-malariapartner drug. Disclosed herein is KAF156, or a pharmaceuticallyacceptable salt thereof, for use in preventing or treating malaria, ordelaying the symptoms or ameliorating the conditions associated withmalaria, wherein the compound is administered daily at a dose of about200 mg to about 1000 mg for up to 5 days, e.g. 1 to 3 days, e.g. 1 or 2days. In particular is disclosed KAF156, or a pharmaceuticallyacceptable salt thereof, for use in preventing or treating malaria, ordelaying the symptoms or ameliorating the conditions associated withmalaria, wherein the compound is administered daily at a dose of about200 mg to about 350 mg for up to 5 days, e.g. 1 to 3 days, e.g. 1 or 2days.

The invention provides methods of preventing or treating malaria,delaying the symptoms or ameliorating the conditions associated withmalaria, comprising daily administering (e.g. once daily) to a subjectin need thereof a therapeutically effective amount of animidazolepiperazine, e.g.2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone(KAF156), or a pharmaceutically acceptable salt thereof optionally incombination with another anti-malaria drug, e.g. lumefantrine.

Disclosed herein are methods of preventing or treating malaria, ordelaying the symptoms or ameliorating the conditions associated withmalaria, comprising daily administering (e.g. once daily) to a subjectin need thereof a dose of2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone(KAF156), or a pharmaceutically acceptable salt thereof, wherein thedose is of about 200 mg to about 1000 mg and is administered for up to 5days, e.g. 1 to 3 days, e.g. 1 or 2 days. For example are disclosedmethods of preventing or treating malaria, or delaying the symptoms orameliorating the conditions associated with malaria, comprising dailyadministering (e.g. once daily) to a subject in need thereof a dose ofKAF156, or a pharmaceutically acceptable salt thereof, wherein the doseis of about 200 mg to about 350 mg and is administered for up to 5 days,e.g. 1 to 3 days, e.g. 1 or 2 days.

Disclosed herein are also improved formulations of lumefantrine, e.g.with enhanced bioavailability versus lumefantrine capsules, and the useof such formulations in combination with KAF156, e.g. with specificregimen of KAF156.

In another aspect, the invention provides an imidazolepiperazine, e.g.2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone(KAF156), or a pharmaceutically acceptable salt thereof, for use inpreventing or treating malaria, or delaying the symptoms or amelioratingthe conditions associated with malaria, wherein saidimidazolepiperazine, e.g. KAF156, is administered daily (e.g. oncedaily) at a dose of about 200 mg to about 1000 mg, e.g. for up to 5days, e.g. for 1 to 3 days. For example, there is provided KAF156, or apharmaceutically acceptable salt thereof, for use in preventing ortreating malaria, or delaying the symptoms or ameliorating theconditions associated with malaria, wherein KAF156 is administered daily(e.g. once daily) at a dose of about 200 mg to about 350 mg, e.g. for upto 5 days, e.g. for 1 to 3 days.

Disclosed herein are doses of KAF156 for use in preventing or treatingmalaria, to be administered daily (e.g. once daily), of about 200 mg toabout 1000 mg, e.g. about 200 mg to about 350 mg (e.g. about 200 mg,about 350 mg, about 400 mg or about 800 mg) of KAF156.

Disclosed herein are pharmaceutical compositions for use in preventingor treating malaria, comprising KAF156, wherein KAF156 is to beadministered daily (e.g. once daily) to a patient at a dose of about 200mg to about 1000 mg, e.g. of about 200 mg to about 350 mg (e.g. about200 mg, e.g. about 400 mg, e.g. about 800 mg), e.g. for up to 5 days,e.g. for 1 to 5 days, e.g. for 2 to 5 days, e.g. 1 to 3 days, e.g. 1 or2 days.

Disclosed herein are uses of KAF156 or a pharmaceutically acceptablesalt thereof, for the manufacture of a medicament for preventing ortreating malaria, characterized in that KAF156 or a pharmaceuticallyacceptable salt thereof is to be administered daily (e.g. once daily) toa patient at a dose of about 200 mg to about 1000 mg (e.g. about 200 mg,about 350 mg, about 400 mg or about 800 mg), e.g. for up to 5 days, e.g.for 1 to 5 days, e.g. for 2 to 5 days, e.g. 1 to 3 days, e.g. 1 or 2days.

The invention further provides therapeutic kits for preventing ortreating malaria, comprising up to 5 daily doses of KAF156 or apharmaceutically acceptable salt thereof, wherein the dose of KAF156 ora pharmaceutically acceptable salt thereof is of about 200 mg to about1000 mg, e.g. of about 200 mg to about 350 mg, e.g. about 200 mg, e.g.about 350 mg, about 400 mg or e.g. about 800 mg.

In some of the above mentioned methods, therapeutic regimens, kits,uses, and pharmaceutical compositions, the imidazolepiperazine, e.g.KAF156 or a pharmaceutically acceptable salt thereof is administeredwith another anti-malaria drug, e.g. lumefantrine, e.g. as a soliddispersion formulation or microemulsion, e.g. solid dispersionformulation of lumefantrine.

Furthermore the invention provides pharmaceutical combinationscomprising i) an imidazolepiperazine, e.g. KAF156 or a pharmaceuticallyacceptable salt thereof, and ii) another anti-malaria drug, e.g.lumefantrine; and such pharmaceutical combinations for use in preventingor treating malaria, or in delaying the symptoms or ameliorating theconditions associated with malaria. In particular there is providedpharmaceutical combinations comprising about 200 mg to 800 mg of KAF156and about 400 mg to 1000 mg of lumefantrine. For example, there areprovided pharmaceutical combinations comprising about 200 mg to 800 mgof KAF156 and about 400 mg to 1000 mg of lumefantrine, whereinlumefantrin is in form of a solid dispersion formulation ormicroemulsion, e.g. a solid dispersion formulation.

In particular there are provided fixed combinations of KAF156 andlumefantrine, e.g. of KAF156 and solid dispersion formulation oflumefantrine.

Various (enumerated) embodiments of the disclosure are described herein.It will be recognized that features specified in each embodiment may becombined with other specified features to provide further embodiments ofthe present disclosure.

Furthermore the invention provides the use of KAF156 for the manufactureof a medicament for treating or preventing malaria, or delaying thesymptoms or ameliorating the conditions associated with malaria, whereinthe medicament is administered daily (e.g. once daily) during 1 to 5days, e.g. 1 to 3 days, and comprises about 200 mg to about 1000 mg ofKAF156.

For example, there is provided the use of KAF156 for the manufacture ofa medicament for treating or preventing malaria, or delaying thesymptoms or ameliorating the conditions associated with malaria, whereinthe medicament is administered once and comprises about 200 mg, about350 mg or about 400 mg of KAF156.

For example, there is provided the use of KAF156 for the manufacture ofa medicament for treating or preventing malaria, or delaying thesymptoms or ameliorating the conditions associated with malaria, whereinthe medicament is administered daily (e.g. once daily) for three daysand comprises about 200 mg, about 350 mg or about 400 mg of KAF156.

Furthermore the invention provides the use of a combination of KAF156and lumefantrine, e.g. a fixed dose combination, for the manufacture ofa medicament for treating or preventing malaria, or delaying thesymptoms or ameliorating the conditions associated with malaria, whereinthe medicament is administered daily (e.g. once daily) and comprisesabout 200 mg of KAF156 and about 480 mg lumefantrine. Lumefantrine maybe in form of a solid dispersion formulation.

In one embodiment, there is provided the use of a combination of KAF156and lumefantrine, e.g. a fixed dose combination, for the manufacture ofa medicament for treating or preventing malaria, or delaying thesymptoms or ameliorating the conditions associated with malaria, whereinthe medicament is administered daily (e.g. once daily) and comprisesabout 200 mg of KAF156 and about 960 mg lumefantrine. Lumefantrine maybe in form of a solid dispersion formulation.

In another embodiment, there is provided the use of a combination ofKAF156 and lumefantrine, e.g. a fixed dose combination, for themanufacture of a medicament for treating or preventing malaria, ordelaying the symptoms or ameliorating the conditions associated withmalaria, wherein the medicament is administered daily (e.g. once daily)and comprises about 400 mg of KAF156 and about 480 mg lumefantrine.Lumefantrine may be in form of a solid dispersion formulation.

In yet another embodiment, there is provided the use of a combination ofKAF156 and lumefantrine, e.g. a fixed dose combination, for themanufacture of a medicament for treating or preventing malaria, ordelaying the symptoms or ameliorating the conditions associated withmalaria, wherein the medicament is administered daily (e.g. once daily)and comprises about 400 mg of KAF156 and about 960 mg lumefantrine.Lumefantrine may be in form of a solid dispersion formulation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 discloses the concentration time profiles of lumefantrinefollowing single dose administration of 480 mg dose under fastingconditions as conventional tablet, SDF variant-1 and SDF variant-2(human study).

FIGS. 2A and 2B describe Lumeantrine exposure in dog study.

FIGS. 3A and 3B describe KAF156 exposure in dog study.

DETAILED DESCRIPTION OF THE INVENTION

KAF156 (which is2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone),is an imidazolepiperazine of formula (i)

It is described in WO2011/006143 (example 412).

Various aspects of the disclosure are described in further detail in thefollowing subsections. All patents, published patent applications,publications, references and other material referred to herein areincorporated by reference herein in their entirety.

The term “comprising” encompasses “including” as well as “consisting,”e.g. a composition “comprising” X may consist exclusively of X or mayinclude something additional, e.g. X+Y.

According to the invention, treatment of malaria may be prophylactic (toprevent or delay the onset of the disease, or to prevent themanifestation of clinical or subclinical symptoms thereof) ortherapeutic suppression or alleviation of symptoms after themanifestation of the disease. Within the meaning of the presentinvention, the term “treat” also denotes to arrest, delay the onset(i.e., the period prior to clinical manifestation of a disease) and/orreduce the risk of developing or worsening a disease. The term “prevent”or “prevention” refers to a partial or complete inhibition ofdevelopment or progression of the disease.

As used herein malaria refers to the diseases induced by Plasmodiumfalciparum, Plasmodium vivax, Plasmodium ovale or Plasmodium malaria,e.g. acute and cerebral malaria, e.g. uncomplicated P. falciparummalaria.

The term “an effective amount” or “therapeutically effective amount” ofan imidazolepiperazine, e.g. KAF156 or a pharmaceutically acceptablesalt thereof, refers to an amount of the imidazolepiperazine, e.g.KAF156 or a pharmaceutically acceptable salt thereof that will elicit abiological or medical response in a patient, for example, reduction orinhibition of a protein activity, or ameliorate symptoms, alleviateconditions, slow or delay disease progression, or prevent a disease,etc. The term “effective amount” or “therapeutically effective amount”is defined herein to refer to an amount sufficient to provide anobservable improvement over the baseline clinically observable signs andsymptoms of the condition treated.

The term “about” or “approximately” shall have the meaning of within10%, more preferably within 5%, of a given value or range.

The term “pharmaceutically acceptable” means a nontoxic material thatdoes not interfere with the effectiveness of the biological activity ofthe active ingredient(s).

The term “daily” refers to administering the drug, e.g. KAF156,lumefantrine, or the pharmaceutical combination comprising KAF156 andlumefantrine, in a daily manner, i.e. every day. It can correspond to aunique administration (once daily, also referred as QD) or severaladministrations a day, such as up to four times a day.

Preferably KAF156 is administered once a day administration. Similarlylumefantrine is preferably administered once a day.

According to the invention, KAF156 (in form of a free base) isadministered at a dose comprised between about 200 mg and about 800 mg,e.g. between about 200 mg and about 600 mg, e.g. between about 200 mgand about 500 mg, e.g. between about 250 mg and about 500 mg, e.g.between about 250 mg and about 450 mg, e.g. between about 200 mg andabout 400 mg. For example, KAF156 (in form of a free base) isadministered at a dose of about 200 mg, about 250 mg, about 300 mg,about 400 mg, about 450 mg, about 500 mg, about 550 mg, or about 600 mg,about 650 mg, about 700 mg, about 750 mg, about 800 mg. In specificembodiments, these doses are for daily administration, e.g. are dailydoses. In other embodiments, these doses are for once dailyadministration.

In some embodiments, there are provided new therapeutic regimens ofKAF156 for use in preventing or treating malaria, comprisingadministering (e.g. daily) a dose of KAF156 of about 200 mg to about 900mg, e.g. about 200 mg to about 800 mg, e.g. about 200 mg to about 600mg, e.g. about 200 mg to about 500 mg, e.g. about 250 mg to about 500mg, e.g. about 250 mg to about 450 mg, e.g. about 200 mg to about 400mg.

For example, the therapeutic regimens of KAF156 for use in preventing ortreating malaria, comprise administering (e.g. daily) a dose of KAF156of about 200 mg, 250 mg, about 300 mg, about 400 mg, about 450 mg, about500 mg, about 550 mg, or about 800 mg.

According to the invention, KAF156 or a pharmaceutically acceptable saltthereof, is administered daily during up to 5 days, e.g. for 1 to 5days, e.g. for 1 to 3 days, e.g. for 2 to 5 days, e.g. for 1 or 2 days,e.g. for one day. In specific embodiments, there is provided a dose ofKAF156 or a pharmaceutically acceptable salt thereof for uniqueadministration, e.g. unique daily administration.

Provided herein are therapeutic kits for use in preventing or treatingmalaria, comprising KAF156 or a pharmaceutically acceptable saltthereof, e.g. doses thereof to be administered daily. Additionally, suchkits may comprise means for administering the imidazolepiperazine, e.g.KAF156 and instructions for use. These kits may contain one (or more)additional anti-malaria agent(s), e.g. lumefantrine.

Accordingly, disclosed herein are therapeutic kits comprising: a) apharmaceutical composition comprising a therapeutically effective amountof an imidazolepiperazine, e.g. KAF156 or a pharmaceutically acceptablesalt thereof; b) means for administering the imidazolepiperazine or apharmaceutically acceptable salt thereof (KAF156) to a patient at riskof or having malaria; and c) instructions providing administering theimidazolepiperazine (e.g. KAF156) to the patient up to five days.

In other embodiments are provided therapeutic kits comprising a) apharmaceutical composition comprising a doses of an imidazolepiperazine,e.g. KAF156 or a pharmaceutically acceptable salt thereof, e.g. about200 mg to about 1000 mg, e.g. about 200 mg, e.g. about 400 mg or e.g.about 800 mg; b) means for administering the imidazolepiperazine or apharmaceutically acceptable salt thereof (KAF156) to a patient at riskof or having malaria; and c) instructions providing administering theimidazolepiperazine (e.g. KAF156) to the patient.

In some embodiments the therapeutic kit comprises doses of theimidazolepiperazine, e.g. KAF156 or a pharmaceutically acceptable saltthereof, e.g. KAF156, for daily administration during up to 5 days, e.g.1 to 5 doses, e.g. 2 to 5 doses, e.g. 1 to 3 doses, e.g. 1 to 2 doses,e.g. one dose. Such doses can be of about 200 mg to about 1000 mg, e.g.about 200 mg, e.g. about 300 mg, e.g. about 305 mg, e.g. about 400 mg ore.g. about 800 mg of KAF156 (as free base).

For example, there are provided therapeutic kits comprising one to fivedoses of KAF156, or a pharmaceutically acceptable salt thereof, fordaily administration, wherein said doses are of about 200 mg to about1000 mg, e.g. about 200 mg, e.g. about 300 mg, about 350 mg, e.g. about400 mg or e.g. about 800 mg of KAF156 (as free base).

In some of the above mentioned methods, therapeutic regimens, kits,uses, and pharmaceutical compositions, the imidazolepiperazine, e.g.KAF156 or a pharmaceutically acceptable salt thereof is administeredwith another anti-malaria drug, e.g. lumefantrine.

According to the invention, the treatment, e.g. KAF156 or a combinationof KAF156 with another anti-malaria agent, should provide adequateparasiticidal serum levels over a period of at least 6-7 days (3parasite life-cycles approximately) in order to achieve curing thepatient.

Accordingly there are provided pharmaceutical combinations comprising i)an imidazolepiperazine, e.g. KAF156 or a pharmaceutically acceptablesalt thereof, e.g. KAF156, and ii) another anti-malaria agent, e.g.lumefantrine.

In some embodiments, there are provided pharmaceutical combinationscomprising KAF156, and ii) another anti-malaria agent, for use inpreventing or treating malaria, wherein KAF156 (as a free base) is to beadministered daily at a dose of about 200 mg to about 1000 mg, e.g.about 200 mg to about 900 mg, e.g. about 200 mg to about 800 mg, e.g.about 200 mg to about 600 mg, e.g. about 200 mg to about 500 mg, e.g.about 200 mg to about 350 mg, e.g. about 200 mg to about 300 mg, e.g.about 250 mg to about 500 mg, e.g. about 250 mg to about 450 mg, e.g.about 250 mg to about 350 mg, e.g. about 200 mg to about 400 mg, e.g.about 300 mg to about 400 mg.

For example there are provided pharmaceutical combinations comprising i)daily doses of KAF156, and ii) another anti-malaria agent, forpreventing or treating malaria, wherein the dose of KAF156 (as freebase) is about 200 mg, about 250 mg, about 300 mg, about 350 mg, about400 mg, about 450 mg, about 500 mg, about 550 mg, or about 800 mg.

In some embodiments, the second anti-malaria agent is selected from thegroup consisting of proguanil, chlorproguanil, trimethoprim,chloroquine, mefloquine, lumefantrine, atovaquone,pyrimethamine-sulfadoxine, pyrimethamine-dapsone, halofantrine, quinine,quinidine, amodiaquine, amopyroquine, sulphonamides, artemisinin,arteflene, artemether, artesunate, primaquine and pyronaridine.

In particular, the second anti-malaria agent is lumefantrine.

Lumefantrine may be in the form of as a solid dispersion formulation.

According to the invention, lumefantrine is to be administered daily ata dose of about 400 mg to 1000 mg, e.g. about 400 mg to about 500 mg,e.g. about 900 mg to about 1000 mg. For example, lumefantrine is to beadministered daily at a dose of about 480 mg or about 960 mg.

According to the invention, imidazolepiperazine, e.g. KAF156 or apharmaceutically acceptable salt thereof, e.g. KAF156, can beadministered prior to, simultaneously with, or after the secondanti-malaria agent, e.g. lumefantrine.

The terms “co-administration” or “combined administration” or the likeas utilized herein are meant to encompass administration of i) animidazolepiperazine, e.g. KAF156 or a pharmaceutically acceptable saltthereof, e.g. KAF156, and ii) the second anti-malaria agent, e.g.lumefantrine, to a single patient, and are intended to include treatmentregimens in which the agents are not necessarily administered by thesame route of administration or at the same time.

The term “pharmaceutical combination” as used herein means a productthat results from the mixing or combining of more than one activeingredient and includes both fixed and non-fixed combinations of theactive ingredients. The term “fixed combination” means that the activeingredients, i.e. the imidazolepiperazine and the second anti-malariaagent, e.g. KAF156 and lumefantrine, are both administered to a patientsimultaneously in the form of a single entity or dosage. The term“non-fixed combination” means that the active ingredients, i.e. theimidazolepiperazine and the second anti-malaria agent, e.g. KAF156 andlumefantrine, are both administered to a patient as separate entitieseither simultaneously, concurrently or sequentially with no specifictime limits, wherein such administration provides therapeuticallyeffective levels of the two compounds in the body of the patient.

In general, the imidazolepiperazine, e.g. KAF156 or a pharmaceuticallyacceptable salt thereof will be administered via any of the usual andacceptable modes known in the art.

The imidazolepiperazine, e.g. KAF156 can be administered aspharmaceutical compositions by any conventional route, in particularenterally, e.g. orally, e.g. in the form of tablets or capsules, orparenterally, e.g. in the form of injectable solutions or suspensions,topically, e.g. in the form of lotions, gels, ointments or creams, or ina nasal or suppository form. Pharmaceutical compositions comprising theimidazolepiperazine, e.g. KAF156, optionally in combination with asecond anti-malaria agent, e.g. lumefantrine, in association with atleast one pharmaceutically acceptable carrier or diluent can bemanufactured in a conventional manner by mixing, granulating or coatingmethods. For example, oral compositions can be tablets or gelatincapsules comprising the imidazolepiperazine, e.g. KAF156, together witha) diluents, e.g. lactose, dextrose, sucrose, mannitol, sorbitol,cellulose and/or glycine; b) lubricants, e.g. silica, talcum, stearicacid, its magnesium or calcium salt and/or polyethyleneglycol; fortablets also c) binders, e.g., magnesium aluminum silicate, starchpaste, gelatin, tragacanth, methylcellulose, sodiumcarboxymethylcellulose and or polyvinylpyrrolidone; if desired d)disintegrants, e.g. starches, agar, alginic acid or its sodium salt, oreffervescent mixtures; and/or e) absorbents, colorants, flavors andsweeteners. Injectable compositions can be aqueous isotonic solutions orsuspensions, and suppositories can be prepared from fatty emulsions orsuspensions. The compositions may be sterilized and/or containadjuvants, such as preserving, stabilizing, wetting or emulsifyingagents, solution promoters, salts for regulating the osmotic pressureand/or buffers. In addition, they may also contain other therapeuticallyvaluable substances. Suitable formulations for transdermal applicationsinclude an effective amount of a compound of the present invention witha carrier. A carrier can include absorbable pharmacologically acceptablesolvents to assist passage through the skin of the host. For example,transdermal devices are in the form of a bandage comprising a backingmember, a reservoir containing the compound optionally with carriers,optionally a rate controlling barrier to deliver the compound to theskin of the host at a controlled and predetermined rate over a prolongedperiod of time, and means to secure the device to the skin. Matrixtransdermal formulations may also be used. Suitable formulations fortopical application, e.g. to the skin and eyes, are preferably aqueoussolutions, ointments, creams or gels well known in the art. Such maycontain solubilizers, stabilizers, tonicity enhancing agents, buffersand preservatives.

According to the invention, lumefantrine can be prepared as a soliddispersion. The term solid dispersion refers to dispersion of an activemolecule in an inert carrier in the solid state prepared by solvent,melting or solvent-melting methods.

Said compositions can be prepared using different processes e.g. solventevaporation, spray drying, melt extrusion, fluid bed granulationtechnology, solvent evaporation, use of polymers, melt cooling. Thetechniques that can be used are known to the one skilled in the art, andare described e.g. in Gahoi et al (Int. J Pharm Sci. Rev. Res. 8 (2),170-175. 2011), Balaji et al (International Journal of Pharmacy andPharmaceutical Sciences, Vol 6 Issue 2, 2014), Fule et al (Int. J. drugdel. 4, 2012, 95-106). The solid dispersion can further be mixed withother excipients and can be formulated into capsule or tablet dosageforms. Excipients that can be used can be e.g. poloxamer 188 (e.g. inhigher amount than the drug, e.g. four times more than the drug amountof drug); poloxamer 407, PEG800, solutol, gelucire, Polyvinylpyrollidone(PVP) (e.g. PVP K30) or basic butylated methacrylate copolymer (e.g.Eudragit EPO). Preferably, the solid dispersion of lumefantrinecomprises excipients selected from the group consisting of Solupus,Eudragit EPO, PVP K30 and mixture thereof, e.g. selected from the groupconsisting of Eudragit EPO, PVP K30 and mixture thereof.

The term solid dispersion refers to a group of solid products consistingof at least two different components, generally a hydrophilic matrix anda hydrophobic drug. Herein is described the preparation of soliddispersions using hydrophilic carriers, such as e.g.polyvinylpyrrolidone (Povidone, PVP), polyethylene glycols (PEG 6000),Surfactants like Tween-80, Poloxamer, and Sodium Lauryl Sulphate (SLS).

According to the invention, lumefantrine can be prepared as amicroemulsion, e.g. as described in Patel (DARU J. Pharm. Sci, 21 (27),2013).

According to the invention, lumefantrine can be in amorphous state.

According to the invention, there are provided pharmaceuticalcombination comprising about 200 mg of KAF156 (as free base), and about400 mg to 500 mg of lumefantine (as free base), e.g. about 480 mglumefantrine (as free base), for daily administration.

According to the invention, there are provided pharmaceuticalcombination comprising about 300 mg or 350 mg of KAF156 (as free base),and about 400 mg to 500 mg of lumefantine (as free base), e.g. about 480mg lumefantrine (as free base), for daily administration.

According to the invention, there are provided pharmaceuticalcombination comprising about 400 mg of KAF156 (as free base) and about400 mg to 500 mg of lumefantine (as free base), e.g. about 480 mglumefantrine (as free base), for daily administration.

According to the invention, there are provided pharmaceuticalcombination comprising about 800 mg of KAF156 (as free base) and about400 mg to 500 mg of lumefantine (as free base), e.g. about 480 mglumefantrine (as free base), for daily administration.

According to the invention, there are provided pharmaceuticalcombination comprising about 200 mg of KAF156 (as free base) and about900 mg to 1000 mg of lumefantine (as free base), e.g. about 960 mglumefantrine (as free base), for daily administration.

According to the invention, there are provided pharmaceuticalcombination comprising about 300 mg or 350 mg of KAF156 (as free base)and about 900 mg to 1000 mg of lumefantine (as free base), e.g. about960 mg lumefantrine (as free base), for daily administration.

According to the invention, there are provided pharmaceuticalcombination comprising about 400 mg of KAF156 (as free base) and about900 mg to 1000 mg of lumefantine (as free base), e.g. about 960 mglumefantrine (as free base), for daily administration.

According to the invention, the pharmaceutical combinations comprisingKAF156 and lumefantine (e.g. as described hereinabove) are fixed dosecombinations. In such a fixed dose combination, lumefantrine can beformulated as a solid dispersion formulation.

It is understood that the examples and embodiments described herein arefor illustrative purposes only and that various modifications or changesin light thereof will be suggested to the persons skilled in the art andare to be included within the spirit and purview of this application andscope of the appended claims. All publications, patents, and patentapplications cited herein are hereby incorporated by reference for allpurposes.

EXAMPLES Example 1: Lumefantrine Solid Dispersion Capsule Composition

Ingredient mg/unit % w/w Lumefantrine drug substance 75.000 18.75Polyvinylpyrollidone K30 120.000 26.25 Eudragit EPO 105.000 26.25Croscarmellose sodium 64.000 16.00 Microcrystalline cellulose 30.0007.50 Poloxamer 188 15.000 3.75 Colloidal Silicon dioxide 4.000 1.00Magnesium stearate 2.000 0.50 Total capsule fill 400.000 100.00

Example 2: Lumefantrine Solid Dispersion (SD) Capsule Composition

Ingredient mg/unit % w/w Lumefantrine drug substance 75.000 18.75Polyvinylpyrollidone K30 120.000 30.00 Eudragit EPO 105.000 26.25Croscarmellose sodium 64.000 16.00 Microcrystalline cellulose 30.0007.50 Colloidal Silicon dioxide 4.000 1.00 Magnesium stearate 2.000 0.50Total capsule fill 400.00 100.00The compositions of Examples 1 and 2 have shown significantly higherdissolution at pH 1 and pH2 in presence and in absence of a surfactant.

Example 3: Lumefantrine Microemulsion Composition

Ingredient mg/unit % w/w Lumefantrine drug substance 150.000 10.00 Oleicacid 596.700 39.78 Cremophore EL 596.700 39.78 Triethylcitrate 149.1009.94 Butylated hyroxytoluene 7.500 0.50 Total 1500.000 100.00As can be seen in the table below, the presence of butylatedhydroxytoluene as a stabilizer at a level of 0.5% has resulted insignificant improvement in the stability of the microemulsions which isevident by the decreased levels of Lumefantrine step-4 impurity.Stability data at 4 week time point for microemulsion

Microemulsion with Microemulsion without butylated butylatedHydroxyltoluene hydroxyltoluene Assay Lumefantrine Assay LumefantrineCondition (%) step-4 (%) (%) step-4 (%) Initial 101.9 0.18 103.6 0.00 5° C. 87.5 0.00 75.4 27.42 25° C., 60% R.H 94.4 0.00 62.5 32.24 50° C.,75% R.H 74.6 0.22 59.7 19.04

Example 4

Bioavailability of the solid dispersion capsule formulation was assessedin male beagle dogs along with the conventional tablet(composition/process similar to Coartem®) and microemulsion.

Formulation tested in dogs: Dosing information for administrationFormulation of 150 mg Tablet¹ Lumefantrine 150 mg tablet Soliddispersion capsules² Lumefantrine 7 mg HGC (2 capsules to beadministered) Microemulsion Lumefantrine 10% w/w microemulsion (1.5 gmicroemulsion contains 150 mg lumefantrine) ¹Composition/process similarto Coartem ® ²Corresponds to the composition of example 2.

The plasma profile and pharmacokinetic parameters (table below) fromthis study showed almost 4 fold and 9 fold higher Lumefantrine exposurefrom solid dispersion capsule and microemulsion in comparison to theconventional tablet. Lumefantrine-SD capsule has an improved absorptionprofile and less food effect, leading to exposure which allows for aonce-daily regimen.

Lumefantrine Pharmacokinetics (PK) Data from the Dog Study:

Cmax AUC_(last) AUC_(inf) T_(max) Formulation (ng/ml) (μg · h/ml) (μg ·h/ml) (h) Tablet 1580 ± 491  10.2 ± 7.8  14.8 ± 4.65 4 (2-4) Soliddispersion 3380 ± 2380 41.7 ± 31.6 43.1 ± 32.7 6 (4-6) Capsule ¹Microemulsion 9720 ± 4000 89.1 ± 46  91.3 ± 46.7 4 (2-4) ¹ Correspondsto the composition of example 2. ² Corresponds to the composition ofexample 3.

Example 5

The pharmacokinetics of the two SD capsule variants described inExamples 1 and 2 above (that both contain lumefantrine in amorphousform) was assessed in a randomized, open-label, sequential two-partsstudy in healthy volunteers. In Part 1, relative bioavailability of thetwo SDF variants was compared with conventional formulation (120 mgconventional tablet) after single dose administration of 480 mg underfasted conditions in three parallel cohorts.

An interim internal review was conducted after approximately 12 subjectsfrom each cohort had completed study (Day 12) to determine if thelumefantrine SD capsules variants met protocol specified criterion(enhanced lumefantrine bioavailability >4 fold) to continue into Part 2.

In Part 2, which followed a washout period of 5 weeks, the same subjectswere reallocated to a 480 mg food effect arm or a higher dose arm (960mg dose) in a 1:1 ratio. After dosing, subjects were followed for 12days (Days 53-64) before a final end-of-study (EOS) visit by Day 71(approximately).

For fasting treatments, subjects had no food or liquid (except water)for at least 10 hours prior to administration of study drug andcontinued to fast for at least 4 hours post dose. For the fedtreatments, subjects were provided a high fat breakfast (total of 916calories with 178, 241, and 497 calories from protein, carbohydrate, andfat, respectively). The meal was served and consumed within 30 minutesand study drug was administered within 5 minutes after completion of themeal. All doses were administered with 180-240 mL water.

The study population comprised healthy male subjects of at least 50 kgin weight (BMI within 18.0-30.0 kg/m2). A total of 49 male subjects(18-44 years) were randomized into Part 1 of the study and of these, 16subjects continued into Part 2 of the study.

Pharmacokinetic (PK) Assessment:

All blood samples were taken by either direct venipuncture or anindwelling cannula inserted in a forearm vein. PK samples were obtainedand evaluated in all subjects at all dose levels. Blood samples for PKanalysis of lumefantrine were collected at pre-dose and 1, 2, 4, 5, 6,8, 10, 12, 24, 36, 48, 72, 120, 168, 216, and 264 hours post-dose.

Lumefantrine concentration was determined by a validated Liquidchromatography-Mass spectrometry (LC-MS/MS) method with a Lower Limit ofQuantification (LLOQ) of 50 ng/mL. Briefly, the bioanalytical methodconsisted of protein precipitation followed by solid phase extraction ofhuman plasma samples and analysis of diluted samples by LC-MS/MS inMultiple Reaction Monitoring (MRM) positive mode using ElectrosprayIonization (ESI) as the ionization technique. The lower and upper limitsof quantification for linear range were 50.0 ng/mL and 20000 ng/mLrespectively using 10 μL of human plasma. Lumefantrine in human plasmais stable for 44 hours at room temperature; 9 months at <−70° C.; 3freeze/thaw cycles at <−70° C. The extract is stable for 100 hours in anautosampler at 8° C. The stability data could cover the period fromsampling to analysis of all study samples. For eight points calibrationconcentrations (50, 100, 200, 500, 2000, 5000, 16000 and 20000 ng/mL)bias was within the range of ±15.0% at all concentrations except forLLOQ (50 ng/mL) for which it was within the range of ±20.0%. For qualitycontrol samples (150 ng/mL, 2500 ng/mL and 15000 ng/mL) bias was withinthe range of ±15.0% for at least ⅔ of the individual values.

Concentrations below the LLOQ were considered as “zero” forpharmacokinetic analysis. The following pharmacokinetic parameters weredetermined from the plasma concentration-time data by non-compartmentalanalysis in Phoenix WinNonlin (Version 6.4): C_(max), T_(max),AUC_(0-72 h), AUC_(last), AUC_(inf), T_(1/2), Vz/F and CL/F. The lineartrapezoidal rule was used for AUC calculation.

Statistical Methods:

Sample size: Part 1: 36 subjects (12 per cohort) had complete data fromeach cohort for which would allow adequate detection of at least a1.5-fold change. For the observed ratios from 1.5 to 5.0-fold change thepredicted 90% confidence intervals for the primary pharmacokineticparameter ratio (AUC_(inf), AUC_(last.) and C_(max) based on logtransformation) are: 1.5 (1.08, 2.09), 2.0 (1.44, 2.78), 3.0 (2.15,4.18), 4.0 (2.87, 5.57), 5.0 (3.59, 6.96) using the historic data onvariability. In Part 2, no formal statistical calculations wereconsidered in calculating the sample size.

The log transformed primary pharmacokinetic parameters C_(max),AUC_(last) and AUC_(inf) were analyzed separately by using a lineareffects model with treatment as fixed effects. The estimated mean and90% confidence intervals of treatment difference were back transformedto obtain the geometric mean ratio and 90% confidence intervals of theratio and those were reported to represent the relative bioavailabilityof SD formulation(s) variant-1 vs. conventional tablet and SDF variant-2vs. conventional tablet.

To assess the pharmacokinetics of higher single dose of 960 mg incomparison to single dose of 480 mg log transformed primarypharmacokinetic Parameters (C_(max), AUC_(last) and AUC_(inf)) werecompared using fixed effects model with treatment and subject as fixedeffects. The estimated mean and 90% confidence intervals of treatmentdifference were back transformed to obtain the geometric mean ratio and90% confidence intervals of the ratio and those were reported torepresent the exposure of SD formulation(s) at 960 mg single dosestrength, using 480 mg dose as reference.

An exploratory assessment of food effect between fasted and fedtreatments were evaluated for log transformed primary pharmacokineticparameters (C_(max), AUC_(last) and AUC_(inf)) using a fixed effectsmodel with treatment and subject as fixed effects. The estimated meanand 90% confidence intervals of treatment difference were backtransformed to obtain the geometric mean ratio and 90% confidenceintervals of the ratio and those were reported to represent the relativebioavailability under fed conditions relative to fasted condition.

Results:

The concentration time profiles of lumefantrine following single doseadministration of 480 mg dose under fasting conditions as conventionaltablet, SDF variant-1 and SDF variant-2 are presented in FIG. 1 .Summary pharmacokinetic parameters corresponding to FIG. 1 are presentedin Table below:

Cohort 1 Cohort 2 Cohort 3 Cohort 4 Cohort 6 Cohort 5 Cohort 7 (480 mg(480 mg SD (480 mg SD (480 mg SD (480 mg SD (960 mg SD (960 mg SDconventional variant-1 variant-2 variant-1 variant-2 variant-1 variant-2tablets, capsules, capsules, capsules, capsules, capsules, capsules,Parameter fasting) fasting) fasting) fed) fed) fasting fasting) (unit) #N = 16 N = 16 N = 16 N = 4 N = 4 N = 4 N = 4 C_(max) 260 ± 143 4790 ±1680 3780 ± 2130 29700 ± 10900 19800 ± 346   8410 ± 3970 7280 ± 2180(ng/mL) [55.0] [35.0] [56.5] [36.8]  [1.7] [47.2] [30.0] (n = 16) (n =16) (n = 16) (n = 3) (n = 3) (n = 4) (n = 3) AUC_(last) 3.08 ± 2.66  112± 48.9 70.7 ± 50.6 568 ± 183 477 ± 76.2 187 ± 117  121 ± 77.6 (h ×μg/mL) [86.2] [43.8] [71.6] [32.3] [16.0] [62.4] [64.2] (n = 16) (n =13) (n = 15) (n = 4) (n = 3) (n = 3) (n = 4) AUC_(inf) 7.15 ± 2.27  117± 48.6 82.2 ± 50.8 599 ± 206 496 ± 66.2 219 ± 113  129 ± 83.5 (h ×μg/mL) [31.7] [41.6] [61.8] [34.3] [13.3] [51.8] [64.8] (n = 6)  (n =15) (n = 15) (n = 4) (n = 4) (n = 4) (n = 4) AUC_(0-24 h) 2.80 ± 1.8957.6 ± 22.9 42.8 ± 24.9  290 ± 96.7 261 ± 21.3  107 ± 52.0 71.9 ± 38.9(h × μg/mL) [67.3] [39.7] [58.0] [33.4]  [8.2] [48.8] [54.1] (n = 16) (n= 16) (n = 16) (n = 4) (n = 4) (n = 4) (n = 4) AUC_(0-72 h) 3.51 ± 2.7487.1 ± 35.6 61.8 ± 37.3 435 ± 142 388 ± 39.7  162 ± 81.0  104 ± 60.0 (h× μg/mL) [77.9] [40.8] [60.3] [32.7] [10.2] [50.1] [57.7] (n = 16) (n =16) (n = 16) (n = 4) (n = 4) (n = 4) (n = 4) T_(max)(h) 6.00 6.00 6.006.00 8.00 8.00 6.00 (5.00-10.0) (6.00-10.0) (6.00-10.0) (6.00-8.00)(5.00-8.03) (6.00-10.0) (6.00-10.0) (n = 16) (n = 16) (n = 16) (n = 3)(n = 3) (n = 4) (n = 3) T½ (h) 14.2 ± 5.17 76.5 ± 27.3 53.0 ± 38.3 73.7± 15.5 94.2 ± 30.2   115 ± 46.7 58.1 ± 44.8 [36.5] [35.6] [72.2] [21.0][32.0] [40.6] [77.2] (n = 6)  (n = 15) (n = 15) (n = 4) (n = 4) (n = 4)(n = 4) CL/F (L/h) 71.9 ± 18.4 5.53 ± 4.72 7.95 ± 4.52 0.869 ± 0.2660.980 ± 0.121  5.37 ± 2.60 10.9 ± 7.66 [25.5] [85.3] [56.8] [30.6][12.4] [48.5] [70.3] (n = 6)  (n = 15) (n = 15) (n = 4) (n = 4) (n = 4)(n = 4) Vz/F (L) 1360 ± 259  500 ± 190 444 ± 120 88.2 ± 12.2 135 ± 54.3824 ± 366 625 ± 133 [19.0] [38.1] [27.0] [13.8] [40.4] [44.4] [21.3] (n= 6)  (n = 15) (n = 15) (n = 4) (n = 4) (n = 4) (n = 4) n = number ofsubjects with non-missing values within the parameter #All values arepresented as mean ± SD[CV %] (n), except T_(max) which is presented asmedian (range).

Irrespective of the formulation, lumefantrine was absorbed with medianT_(max) of 6 hours with some initial lag time.

The geometric mean ratios and 90% CIs for C_(max), AUC_(last) andAUC_(inf) for both SD formulations variant-1 and variant-2 relative tothe conventional tablet (Reference) are presented in Table below.

Treatment Comparison Adjusted Geo-mean Parameter Treatment N* Geo-meanComparison ratio (90% CI) AUC_(inf) Cohort 1 6 6.90 (h × μg/mL) Cohort 215 104.46 Cohort 2 vs Cohort 1 15.15  (9.79, 23.44) Cohort 3 15 70.12Cohort 3 vs Cohort 1 10.17  (6.57, 15.73) AUC_(last) Cohort 1 16 2.02 (h× μg/mL) Cohort 2 13 97.47 Cohort 2 vs Cohort 1 48.19 (26.02, 89.23)Cohort 3 15 49.07 Cohort 3 vs Cohort 1 24.26 (13.41, 43.90) C_(max)Cohort 1 16 224.50 (ng/mL) Cohort 2 16 4376.88 Cohort 2 vs Cohort 119.50 (13.12, 28.97) Cohort 3 16 3014.73 Cohort 3 vs Cohort 1 13.43 (9.04, 19.96)The log transformed primary pharmacokinetic parameters of C_(max),AUC_(last) and AUC_(inf) were analyzed separately by using a linearmixed effects model with treatment (cohort) as fixed effect.n*=number of subjects with non-missing valuesReference: Cohort 1: 480 mg conventional tablets (Fasting)Test-1: Cohort 2: 480 mg SD variant-1 capsules (Fasting)Test-2: Cohort 3: 480 mg SD variant-2 capsules (Fasting)

The rate and extent of absorption of lumefantrine from both the SDformulations was enhanced significantly relative to conventionalformulation. The C_(max) for SD formulation variant-1 was 47.9 μg/mL.The C_(max) for SD formulation variant-1 and SD formulation variant-2was about 19-fold and about 13-fold higher respectively, compared toconventional formulation under fasting conditions.

The bioavailability (through AUC_(last)) of lumefantrine from SDformulation variant-1 and variant-2 increased up to about 48-fold andabout 24-fold, respectively, relative to conventional formulation.

Furthermore, both variants demonstrated positive food effect and lessthan proportional increase in exposure between 480 mg and 960 mg doses.The SD formulations achieved considerable increase in bioavailabilitywithout the need to be administered with food rich in fat.

The results show that SD formulation enhances lumefantrinebioavailability to a significant extent.

Example 6

The study design is described in the table below. To stimulate gastricsecretion, each animal (dog) received a single 6-μg/kg intramuscularinjection of pentagastrin approximatively 60 minutes prior to testarticle administration. Washout between each treatment wasapproximatively 7-8 days.

Number Target Dose Target Dose Phase/ of Male Dose Level Volume GroupAnimals Test Article Route (mg/animal) (mL/animal) 1/1 3 Lumefantrinesuspension Oral 150^(a) 40 (updated variant SD) 2/1 3 Luinefantrine-SDFsachet Oral 15^(b)and 100^(c) 5^(bd) and 1^(cf) and KAF156 tablet (FCT)3/1 3 Luniefantrine-SDF capsule Oral 150^(e) 2^(eg) 4/1 3Lumefantrine-SDF sachet Oral  15^(b) 5^(bd) 5/1 3 KAF156 tablet (FCT)Oral 100^(c) 1^(cf) ^(a)Lumefantrine suspension dose is 600 mg(containing 25% drug load) in 40 mL/animal or 150 mg/animalLumefantrine. ^(b)Lumefantrine-SD sachet suspension dose is 3.37 g(containing 17.78% drug load) in 199 mL vehicle (or 16.9 mg/mL) and willbe dosed at 3 mg/mL (LUM566), 15 mg/kg, and 5 mL/kg. ^(c)The dose ofKAF156 will be 100 mg (1 × 100 mg). dUnits are mL/kg. ^(e)The dose ofLumefantrine will be 150 mg (2 × 75 mg capsules). ^(f)Units aretablets/animal. ^(g)Units are capsules/animal.

The pharmacokinetic data of lumefantrine are presented in the tablebelow:

The results as indicated in the table above and in FIGS. 2A and 2B showthat lumefantrine exposure is increased by around 1.5 fold whenadministered together with KAF156.

Unanticipatedly KAF156 exposure is also increased when co-administeredwith LUM-SD formulation, by 2 to 3-fold (mean) (see FIGS. 3A and 3B, andtable below).

Phase 2 (Combo) Phase 5 (Mono) KAF156 Mean SD Mean SD T½ (h) 31.0 8.633.2 6.5 Tmax (h) 3.3* 4.0 1.0 0.0 Cmax (ng/mL) 1204 465 451 213 AUClast(h*ng/mL) 36710 7382 11632 5472 AUCinf (h*ng/mL) 45360 5394 14435 6130*T_(max) were 1, 1, 8 hr in 3 dogs, respectively.

Ratio (Phase 2:Phase 5) KAF156 Dog 1 Dog 2 Dog 3* Mean SD Cmax 2.6 2.53.3 2.8 0.4 AUClast 2.7 2.9 5.2 3.6 1.4 AUCinf 2.6 2.8 5.3 3.6 1.5T_(1/2) T_(max) C_(max) C_(max)/D AUC_(last) AUC_(INF) AUC_(INF)/D (h)(h) (ng/mL) (ng/mL/mg) (h*ng/mL) (h*ng/mL) (h*ng/mL/mg) Phase 2 (SDsachet co- 19.1 ± 7.4 4 ± 0 4110 ± 487 274 ± 32.5 36400 ± 6606  37317 ±6425  2488 ± 428 dosed with KAF156) Phase 4 (SD sachet) 23.8 ± 9.2 3.3 ±1.2 1910 ± 401 127 ± 26.7 24380 ± 11968 25443 ± 11816 1696 ± 788 *dog 3had emesis after dosing in Phase 5, i.e., possible dose lose

When KAF156 is co-administrated with lumefantrine, both lumefantrine andKAF156 exposures significantly increased.

Example 7: Population Pharmacokinetics Model

One population PK model for KAF156 and one population PK model forLUM-SDF variant 1 were implemented in Monolix 4.4.0 as part of MonolixSuite 2016R1 (Lixoft, Paris, France) using the SAEM algorithm.Simulations were performed using simulx function of mlxR 3.1.0 packagein R-3.2.3. The final models were used to perform simulations fordifferent dosing regimens. Individual PK profiles for KAF156 and LUM-SDFvariant-1 up to 500 hours under different combination regimens weresimulated using the final models. Summary statistics for concentrationon day 6 and day 7, proportion of patients who have concentration on day7 above 200 ng/mL for LUM-SDF variant-1, proportion of patients who haveconcentrations on day 6 and on day 7 above 58 ng/mL for KAF156, C_(max),AUC_(inf) were calculated. Likelihood of success of a given LUM-SDFvariant-1 dose level was calculated as the percentage of patientsreceiving this given dose who have lumefantrine day 7 plasmaconcentrations above 200 ng/mL; likelihood of success of a given KAF156dose level was calculated as the percentage of patients receiving thisgiven dose who have KAF156 day 6 plasma concentrations above 58 ng/mL.The likelihood of combination treatment success was calculated assumingindependent effects of its components without any synergetic effect.

For the PK simulations of different combination regimens,inter-individual variability was taken into account; residualvariability was not taken into account. Estimated covariance matrices ofthe random effects (“Omega matrices”) were used. Parameter uncertaintywas not taken into account for the simulations, i.e. point estimates ofmodel parameters were used. Body weight effect was taken into accountfor the simulations. Dose proportionality was assumed for thesesimulations. The likelihood of combination treatment success wascalculated assuming independent effects of its components without anysynergetic effect between KAF156 and lumefantrine asptot=1−(1−p1)(1−p2), where p1 is the likelihood of success for KAF156and p2 is the likelihood of success for lumefantrine.

Results: The simulation outcome for the exposure and probability oftreatment success are presented in below Tables A and B, respectively.

TABLE A Simulated exposure of KAF156 and lumefantrine and combinationtreatment: Likelihood of Lumefantrine day 7, KAF156 day 6 combinationDose/regimen concentrations, ng/mL concentrations, ng/mL treatmentsuccess KAF156 400 mg + LUM-SDF 162 [73-387]  32 [13-81] 45% 960 mg QDfor 1 day KAF156 800 mg + LUM-SDF 162 [73-387]   63 [26-162] 72% 960 mgQD for 1 day KAF156 400 mg + LUM-SDF 358 [160-859]  80 [34-195] 97% 960mg QD for 2 days KAF156 200 mg + LUM-SDF 383 [173-888]  75 [33-178] 97%480 mg QD for 3 days KAF156 400 mg + LUM-SDF 383 [173-888] 150 [65-356]100%  480 mg QD for 3 days KAF156 400 mg + LUM-SDF  602 [267-1439] 150[65-356] 100%  960 mg QD for 3 days

TABLE B The likelihood of treatment success: Likelihood of combinationLUM-SDF KAF156 treatment Dose/regimen alone alone success KAF156 400mg + LUM-SDF 34% 16% 45% 960 mg QD for 1 day KAF156 800 mg + LUM-SDF 34%57% 72% 960 mg QD for 1 day KAF156 400 mg + LUM-SDF 89% 72% 97% 960 mgQD for 2 days KAF156 200 mg + LUM-SDF 91% 70% 97% 480 mg QD for 3 daysKAF156 400 mg + LUM-SDF 91% 97% 100%  480 mg QD for 3 days KAF156 400mg + LUM-SDF 98% 97% 100%  960 mg QD for 3 days

The simulations suggest that under fasting conditions, the 3-day dosesand the 2-day doses of KAF156 and LUM-SDF combinations have a relativelyhigh likelihood of success (at least 97%). High single dose regimenKAF156 800 mg+LUM-SDF 960 mg QD for 1 day has a lower likelihood ofsuccess (72%), as well as the low single dose regimen KAF156 400mg+LUMSDF 960 mg QD for 1 day (45%).

Example 8: Open-Label, Randomized, Parallel-Group Study in Adults andChildren with Confirmed and Uncomplicated P. falciparum Malaria

This study is set up in a two-part sequential design.

Part A:

Approximately 325 male and female adult/adolescent patients (≥12 yearsold and ≥35.0 kg) will be enrolled in Part A of the study.

At screening, eligible patients will be randomized into one of the sevencohorts, i.e., six KAF156 and LUM-SDF (Solid Dispersion Formulation)dose combinations and a control arm, in 2:2:2:2:2:2:1 ratios:

Cohort 1: KAF156 400 mg and LUM-SDF 960 mg once daily (QD) for 1 day

Cohort 2: KAF156 800 mg and LUM-SDF 960 mg QD for 1 day

Cohort 3: KAF156 400 mg and LUM-SDF 960 mg QD for 2 days

Cohort 4: KAF156 200 mg and LUM-SDF 480 mg QD for 3 days

Cohort 5: KAF156 400 mg and LUM-SDF 480 mg QD for 3 days

Cohort 6: KAF156 400 mg and LUM-SDF 960 mg QD for 3 days

Cohort 7: Coartem® twice a day (BID) for 3 days (dosing as per productlabel).

The infection will be measured through PCR-corrected adequate clinicaland parasitological response (ACPR). PCR-Uncorrected ACPR at Days 15, 29and 43 (i.e. 14, 28 and 42 days postdose), and PCR-corrected ACPR atDays 15 and 43 (i.e. 14 and 42 days post-dose) will be performed.Incidence rate of recrudescence and reinfection at Days 15, 29 and 43will be measured, as well as Parasite and Fever Clearance Times (PCT andFCT). Proportion of patients with parasitaemia at 12, 24, and 48 hoursafter treatment will be estimated.

Part B:

Approximately up to 175 children (2 to <12 years old and ≥10.0 kg) withuncomplicated P. falciparum malaria will be randomized to up to threeKAF156 and LUM-SDF dose combinations and the control arm in 2:1 ratios(2 patients for each KAF156 and LUM-SDF dose combination and 1 patientfor control).

Eligible patients will be enrolled into one out of the up to four dosingcohorts i.e. up to three investigational drug dosing arms and a controlarm. Dosing will be adjusted based on children's body weight similar tothe adjustment of Coartem®.

-   -   KAF156 and LUM-SDF: up to 3 cohorts selected depending on the        outcome of Part A—Coartem® BID for 3 days

Initially, 4-6 children in the age range of 6 to <12 years will beincluded in Part B to confirm that KAF156 and LUM-SDF PK/drug exposureis consistent with Part A and that the assumption in dosing is correctin these cohorts. Following confirmation of drug exposure in thesechildren, the additional patients will be included in Part B of thestudy.

Study design, procedures and assessments are the same in Part A and Part

Inclusion Criteria

Patients eligible for inclusion in this study must fulfill all of thefollowing criteria:

Demography:

Part A: male and female patients ≥12 years and with a body weight ≥35.0kg

Part B: after determining the effective/tolerated doses and regimens inadolescent and adult patients, male and female patients ≥2 and <12 yearsand with a body weight ≥10.0 kg will be included

Health Status:

Microscopic confirmation of P. falciparum by Giemsa-stained thick andthin films

P. falciparum parasitaemia of more than 1000 and less than 150 000parasites/μL at the time of screening

Axillary temperature ≥37.5° C. or oral/tympanic/rectal temperature≥38.3° C.; or similar history of fever during the previous 24 hours(history of fever must be documented)

Negative pregnancy test for women of child bearing potential (WOCBP)

Exclusion Criteria

Patients fulfilling any of the following criteria are not eligible forinclusion in this study.

Medical history and clinical status:

1. Mixed Plasmodium infections

2. Signs and symptoms of severe malaria according to WHO 2015 criteriaunless characterized by high parasitaemia only

3. Active infections including tuberculosis

4. Patients with concurrent febrile illnesses (e.g., typhoid fever)

5. History of, or current alcohol misuse/abuse defined as five or moredrinks on the same occasion on each of 5 or more days in the past 30days

6. Known relevant liver disease e.g. chronic hepatitis, cirrhosis,compensated or decompensated, history of hepatitis B or C, hepatitis Bor A vaccination in last 3 months, known gallbladder or bile ductdisease, acute or chronic pancreatitis

7. Any confirmed or suspected immunosuppressive or immunodeficientcondition, including human immunodeficiency virus (HIV) infection

8. Severe malnutrition (body mass index (BMI)<16.0 for patients ≥12years, and less than 70% of median normalized WHO reference weight forchildren <12 years)

9. Severe vomiting, defined as more than 3 times in the 24 hours priorto inclusion in the study or severe diarrhea defined as more than 3watery stools per day

10. Pregnant or nursing (lactating) women

11. Sexually active patients not willing to practice effectivecontraception

12. Women of child bearing potential, defined as all womenphysiologically capable of becoming pregnant, unless they are usinghighly effective methods of contraception during dosing and for theduration of the study.

13. Active duodenal ulcer, ulcerative colitis, Crohn's disease, chronic(i.e. >2 weeks) use of non-steroidal anti-inflammatory drugs (NSAIDs)

14. Clinically relevant abnormalities of electrolyte balance whichrequire correction, e.g. hypokalemia, hypocalcemia or hypomagnesemia.

15. Anemia (Hemoglobin level <8 g/dL)

16. Any surgical or medical condition which might significantly alterthe absorption, distribution, metabolism, or excretion of drugs, orwhich may jeopardize the patient in case of participation in the study.The investigator should make this determination in consideration of thepatient's medical history and/or clinical or laboratory evidence of anyof the following:

AST/ALT >2× the upper limit of normal range (ULN), regardless of thelevel of total bilirubin

AST/ALT >1.5 and ≤2×ULN and total bilirubin is >ULN

Total bilirubin >2×ULN, regardless of the level of AST/ALT

17. Resting QTcF >450 ms (males), QTcF >460 ms (females) at screening

18. Creatinine >2×ULN in the absence of dehydration. In the case ofdehydration, the creatinine should be <2×ULN after oral/parenteralrehydration

19. History of malignancy of any organ system (other than localizedbasal cell carcinoma of the skin or in situ cervical cancer), treated oruntreated, within the past 5 years, regardless of whether there isevidence of local recurrence or metastases

20. Known chronic underlying disease such as sickle cell disease, andsevere cardiac, renal, or hepatic impairment

21. Known active or uncontrolled thyroid disease

22. Inability to tolerate oral medication (in tablet and/or liquid form)Interfering substances

23. Patients with prior antimalarial therapy within 2 months ofscreening

24. Use of any antibiotics with antimalarial activity within 4 weeks ofscreening

25. Use of other investigational drugs within 5 half-lives ofenrollment, or within 30 days or until the expected pharmacodynamiceffect has returned to baseline, whichever is longer

26. Patients taking medications prohibited by the protocol

27. Previous participation in any malaria vaccine study or receivedmalaria vaccine in any other circumstance.

The invention claimed is:
 1. A pharmaceutical combination comprisingabout 400 mg to about 1000 mg lumefantrine formulated as a soliddispersion and about 200 mg to about 1000 mg of2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone,or a pharmaceutically acceptable salt thereof.
 2. The pharmaceuticalcombination according to claim 1, comprising about 200 mg, about 400 mgor about 800 mg of2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone,or a pharmaceutically acceptable salt thereof.
 3. The pharmaceuticalcombination according to claim 1, comprising about 400 mg to about 500mg or about 900 mg to about 1000 mg of lumefantrine.
 4. Thepharmaceutical combination according to claim 1, comprising about 480 mgor about 960 mg of lumefantrine.
 5. The pharmaceutical combinationaccording to claim 1, comprising about 200 mg of2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanoneand about 480 mg of lumefantrine.
 6. The pharmaceutical combinationaccording to claim 1, comprising about 400 mg of2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanoneand about 480 mg of lumefantrine.
 7. The pharmaceutical combinationaccording to claim 1, comprising about 400 mg of2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanoneand about 960 mg of lumefantrine.
 8. The pharmaceutical combinationaccording to claim 1, comprising about 800 mg of2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanoneand about 960 mg of lumefantrine.
 9. The pharmaceutical combinationaccording to claim 1, which is a fixed dose combination.
 10. Thepharmaceutical combination according to claim 1, which is a non-fixeddose combination.
 11. A method of preventing or treating malaria, ordelaying the symptoms or ameliorating the conditions associated withmalaria, in a subject in need thereof, comprising administering to saidsubject compound2-amino-1-(2-(4-fluorophenyl)-3-(4-fluorophenylamino)-8,8-dimethyl-5,6-dihydroimidazo[1,2-a]pyrazin-7(8H)-yl)ethanone,or a pharmaceutically acceptable salt thereof, administrated daily at adose of about 200 mg to about 1000 mg, with lumefantrine formulated as asolid dispersion, wherein the lumefantrine is administered daily at adose of about 400 mg to about 1000 mg.
 12. The method according to claim11, wherein said compound is administered at a dose of about 200 mg,about 400 mg or about 800 mg.
 13. The method according to claim 11,wherein said compound is administered daily during 1 to 3 days.
 14. Themethod according to claim 11, wherein the lumefantrine is administereddaily at a dose of about 400 mg to about 500 mg or about 900 mg to 1000mg.
 15. The method according to claim 11, wherein, the lumefantrine isadministrated daily at a dose of 480 mg or 960 mg.
 16. The methodaccording to claim 11, wherein the compound is administered daily at adose of about 200 mg and the lumefantrine is administered daily at adose of about 480 mg.
 17. The method according to claim 11, wherein thecompound is administered daily at a dose of about 400 mg and thelumefantrine is administered daily at a dose of about 480 mg.
 18. Themethod according to claim 11, wherein the compound is administered dailyat a dose of about 400 mg and the lumefantrine is administered daily ata dose of about 960 mg.
 19. The method according to claim 11, whereinthe compound is administered daily at a dose of about 800 mg and thelumefantrine is administered daily at a dose of about 960 mg.
 20. Themethod according to claim 11, wherein the compound and the lumefantrineis used in a non-fixed dose combination.
 21. The method according toclaim 11, wherein the compound and the lumefantrine is used in a fixeddose combination.